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United States Patent | 5,339,301 |
Raaymakers ,   et al. | August 16, 1994 |
A record carrier on which information may be optically recorded and/or read, having a disc-shaped substrate with a spiral or concentric pattern of preformed tracks thereon and a radiation-sensitive layer extending over such track pattern. The tracks are in the form of ridges of substantially constant width and having a periodic radial wobble of a substantially constant mean frequency, which frequency is modulated by a position-information signal identifying the relative positions of the tracks in the track pattern. Apparatus for forming such a track pattern includes means for modulating the radial track wobble in accordance with the position-information signal. Apparatus for reading an information signal recorded on such a record carrier includes an FM demodulator for recovering the position-information signal from variations in the reflected scanning beam produced by the track modulation, and which also recovers from such variations a clock signal corresponding to the mean frequency of such modulation and which is used to control the scanning velocity. Apparatus for recording an information signal on such a record carrier includes an FM demodulator for recovering the position-information signal from variations in the radiation reflected from the tracks during recording.
Inventors: | Raaymakers; Wilhelmus P. M. (Eindhoven, NL); Kuijpers; Franciscus L. J. M. (Eindhoven, NL); Veenis; Aartje W. (Eindhoven, NL); Pasman; Johannes H. T. (Eindhoven, NL); Mulder; Hendricus A. M. (Eindhoven, NL) |
Assignee: | U.S. Philips Corporation (New York, NY) |
Appl. No.: | 099770 |
Filed: | July 29, 1993 |
Oct 06, 1986[NL] | 8602504 | |
Mar 20, 1987[NL] | 8700655 |
Current U.S. Class: | 369/47.12; 369/44.26; 369/47.54; 369/275.3; 369/275.4; 369/278; 386/125 |
Intern'l Class: | G11B 007/00 |
Field of Search: | 369/47,48,50,51,59,124,277,278,275.3,275.4,44.25,44.26,44.34,44.39 360/27,71,72.1,72.2 358/342 |
3962720 | Jun., 1976 | Braat | 369/278. |
3963862 | Jun., 1976 | Bouwhuis. | |
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4238843 | Dec., 1980 | Carasso et al. | 369/59. |
4326282 | Apr., 1982 | Verboom et al. | 369/59. |
4363116 | Dec., 1982 | Kleuters et al. | 369/47. |
4366564 | Dec., 1982 | deHaan et al. | 369/48. |
4513407 | Apr., 1985 | Bricot | 369/277. |
4615753 | Oct., 1986 | Gregg | 369/275. |
4682317 | Jul., 1987 | Tomisawa | 369/59. |
4716560 | Dec., 1987 | Itonaga | 369/44. |
4719594 | Jan., 1988 | Young et al. | 369/277. |
4819223 | Apr., 1989 | Gregg | 369/275. |
Foreign Patent Documents | |||
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